Ore-grinding mill



B. A. MITCH-ELL AND F. G. JANNEY.

ORE GRINDING MILL.

APPLICATION mm FEB. 17, 1911.

1,370,700. Patented Mar. 8,1921.

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.Qfiiumjmvjxvm Jag/s B. A. MITCHELL AND F. G. JANNEY.

ORE GRINDING MILL.

APPLICATION FILED FEB. 17, 1917.

1,370,700. I Patented Mar.8,1921.

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Indium A. mm m G. IN, 01 GARFIELD, UTAH.

I. oan-enmnmo MILL.

Specification of Letters Iatent.

Patented Mar. 8, 1921.

Application flled l'cbruary 17, 1917. Serial No. 149,889.

To all whom it may concern:

Be it known that we, BE1 -IJAM1N A. .MITCHELL, a citizen of the United States, residing at Garfield, in the count of Salt Lake and State of Utah and. RANK G. JANNEY, a citizen of the flmted States, residing at Garfield, in the county of Salt Lake and State of Utah, have 1nvented certain new and useful Improvements in O re- Grinding Mills, of which the following 15 a specification.

This invention relates to ore grinding mills of the class commonly known as ball mills, and its object is to provide forms for the shells andlinings of said mills. The invention herein described is claimed broadly in our co-pending application, Serial No. 149,338, filed February 19, 1917, and the construction of the grate at the outlet end of the mill is claimed in our co-pending a plication, Serial No. 100,341, filed May 2 1916.

In the present invention the shell is composed of interlocking sections which inclose a hollow cylindrical lining in a single piece. This lining bears at one end upon a grate to hold and lock said grate to its seat over an outlet opening in the shell. At the other end it bears upon the opposite head of the shell, said bearing taking place through angularly disposed surfaces adapted to crowd the lining endwise and against the grate whenever any rotation of said llnmg in either direction takes place within the shell. By this means both the grate and lining are automatically locked rigidly in place.

The above features and advantages, as well as others, will be rendered more apparent in the following specification, taken in connection with the accompanying drawings, in which- Figure 1 is a side elevation, partly in section, of a ball mill embodying the essential features of our invention.

Fig. 2 is an end elevation with ortions in section, taken substantially on t e lines 2-2 and 2-2.

Fig. 3 is an edge view in elevation of a fiat circular lining member.

Fig. 4 is a sectional view of the same.

Fig. 5 is a longitudinal section of the hollow cylindrical lining with the intermediate portions of said lining broken away to save space.

Fig. 6 is a fragmentary elevation of a portion of the flat circular lining member shown in Figs. 3 and 4:; and i Fig. 7 is a fragmentary end elevation of a portion of the hollow cylindrical lining.

Referring to the accompanying drawings, it will be seen that the shell of the mill is composed of end portions or members 11 and 12 circular in outline, and a hollow cylindrical portion 10 composed of two or more parts rigidly secured together, as will be described later. Attached to the end members are hollow journal members 13 and 14 suitably mounted in bearings. The journal 14 serves as the inlet opening to the ball mill through which the material is fed in a manner well known. Within the journal 13 is a suitable lining 19, in which is a channel serving as the outlet opening of the ball mill. Communicating with this channel are radial spaces 18, disposed between radial rigs 34. A circular seat or flange 17 has a position surrounding said radial spaces, and a grate or screen 16, having a large-number of fine openings, leads from the interior of the ball mill to the spaces 18.

Within the ball mill, and bearing upon the outer edges of the grate or screen 16 opposite to the seat 17, is a cylindrical lining 15 in one piece. This lining is provided with suitable tubes or ridges 15, which are designed to operate the balls or other grinding elements which are placed in the mill.

At the opposite end of said mill the hollow cylindrical lining 15 bears at its circular face or edge upon the flat circular lining member 20, said latter member being, in turn, fitted and secured to the head 12. The contact surfaces 25 and 26, where the cylindrical lining 15 and the flat circular member 20 make contact with each other, are beveled or inclined, as shown at 21 and 22 in Fig. 3. These surfaces slope in opposite directions, and meet at a common point or line 22. There are two of such oints at diametrically opposite locations 1n said flat circular linlng member, and also in the end of the hollow cylindrical member. Those in the hollow cylindrical mem- .ber are concave, in order properly to receive the convex surfaces in the flat circular member. In other words, the surfaces 21 and 22 are fitted to the surfaces 23 and 24, and are of such form that should the hollow cylindrical member rotate slightly in either direction it will be forced to ride up either of the inclined surfaces 21, 22. This action in position.

The fiat circular member 20 is shouldered at 26 in order to match properly the inner faces of the ridges Between the hollow cylindrical lining 15 and the outer shell 10 are placed blocks or wedges 27, of wood or other suitable material, which swell and rigidly lock the parts in place when said blocks become wet. The shell members are shouldered into the heads 10 and 11 at 28 and 33. Exterior to these shouldered joints are bolts 29, passing through flanges 30 and 31. The bolt holes forsaid bolts are therefore exterior to the joints, and no possibility of leakage from the interior can occur through said bolt holes. In a similar manner the two or more sections of the shell member 10 are shouldered one into the other, as shown in Fig. 2, and the bolts 35 also pass through the flanges 36 and 37 wholly exterior to said shouldered joints.

In the operation and use of our invention it will be clear that any tendency of the heavy balls, or other contents of the mill, to cause a rotation of the hollow cylindrical lining 15, will be immediately checked by the angularly disposed contact surfaces between the cylindrical member 15 and the end lining member 20. Also, any looseness that might occur in the original assembling would be immediately taken up by said rotation. It will cause a tightening and locking effect, due to the very gradual character of the slope in said contact surfaces. It will be seen that any looseness that may occur in said parts'because of the severe usage to which they are commonly subjected will be automatically removed. The tendency of the parts is to become constantly more rigidly locked in position during use.

While we have described our invention with more or less minuteness, and as being embodied in certain precise forms, yet it will be understood that we do not desire to be limited thereto unduly, or any more than is pointed out in the claims. On the contrary, we contemplate all proper changes in form, construction, and arrangement, the omission of certain elements, and the substitution of equivalents, as circumstances may require or necessity render expedient.

We claim 1. The combination in a rotary grinding mill, of a shell having inlet and outlet openings, a grate mounted adjacent said outlet opening, said shell carrying a seat for one side of said grate, and a hollow tubular lining member formed in one piece and extending throughout the length of said mill, said lining member bearing against said grate opposite said seat, and means including an end lining mounted at the other end of said tubular lining for effecting a pressure of said tubular lining upon said grate.

2. The combination in a rotary grinding mill, of a hollow cylindrical shell having end walls, a tubular lining member formed in one piece and extending throughout the length of said shell, means within said shell engaging said tubular. lining at one end, and a circular lining engaging said tubular lining at its other end, said circular lining and said tubular lining having coacting inclined surfaces adapted to set up a locking pressure therebetween upon relative move-.

ment thereof.

3. The combination in a rotary grinding mill, of a hollow cylindrical shell having end Walls, a tubular lining member formed in one piece and extending throughout the length of said shell, means within said shell engaging said tubular linin at one end, a circular lining engaging sai tubular-lining at its other end, said tubular lining having helically inclined surfaces extending in opposite directions at the end thereof adjacent said circular lining, and said circular lining having inclined surfaces extending in opposite directionsadjacent its periphery to coact with the inclined surfaces of said tubular lining.

In testimony whereof, we have subscribed our names.

BENJAMIN A. MITCHELL. FRANK G. JANNEY. Witnesses:

S. M. FOSTER, O. W. KUMROW. 

